Which action is executed by Cisco ACI during the initial fabric setup?

Power On Auto Provisioning (POAP) is a feature used for automating initial configuration of NX-OS devices, but ACI fabric discovery specifically relies on LLDP for topology mapping.

Cisco ACI's spine-leaf architecture uses ECMP (Equal-Cost MultiPath) for forwarding and does not rely on or create a Spanning Tree Protocol (STP) topology, as STP is largely irrelevant and avoided in ACI fabrics.

Cisco ACI's APIC uses Link Layer Discovery Protocol (LLDP) as its primary mechanism to automatically discover the physical leaf and spine switches connected to the fabric, enabling the APIC to build the initial fabric inventory and topology.

While Cisco Discovery Protocol (CDP) is a proprietary Cisco discovery protocol, Cisco ACI fabric discovery primarily uses the industry-standard LLDP for switch discovery and fabric formation.